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[Server][Bug] Pagination of List requests #55

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merged 1 commit into from
Sep 24, 2025
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[Server][Bug] Pagination of List requests #55

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95 changes: 18 additions & 77 deletions phpstan-baseline.neon
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -54,7 +54,6 @@ parameters:
count: 1
path: examples/02-discovery-http-userprofile/server.php


-
message: '#^Method Mcp\\Example\\ManualStdioExample\\SimpleHandlers\:\:getItemDetails\(\) return type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
Expand All @@ -73,7 +72,6 @@ parameters:
count: 2
path: examples/04-combined-registration-http/server.php


-
message: '#^Method Mcp\\Example\\StdioEnvVariables\\EnvToolHandler\:\:processData\(\) return type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
Expand Down Expand Up @@ -266,7 +264,6 @@ parameters:
count: 2
path: examples/07-complex-tool-schema-http/McpEventScheduler.php


-
message: '#^Method Mcp\\Example\\SchemaShowcaseExample\\SchemaShowcaseElements\:\:calculateRange\(\) return type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
Expand Down Expand Up @@ -321,8 +318,6 @@ parameters:
count: 1
path: examples/08-schema-showcase-streamable/SchemaShowcaseElements.php



-
message: '#^Call to an undefined method Mcp\\Capability\\Registry\\ResourceTemplateReference\:\:handle\(\)\.$#'
identifier: method.notFound
Expand All @@ -342,103 +337,49 @@ parameters:
path: src/Schema/Result/ReadResourceResult.php

-
message: '#^Method Mcp\\Capability\\Registry\\ReferenceProviderInterface\:\:getPrompts\(\) invoked with 2 parameters, 0 required\.$#'
identifier: arguments.count
count: 1
path: src/Server/RequestHandler/ListPromptsHandler.php

-
message: '#^Result of && is always false\.$#'
identifier: booleanAnd.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListPromptsHandler.php

-
message: '#^Strict comparison using \!\=\= between null and null will always evaluate to false\.$#'
identifier: notIdentical.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListPromptsHandler.php

-
message: '#^Method Mcp\\Capability\\Registry\\ReferenceProviderInterface\:\:getResources\(\) invoked with 2 parameters, 0 required\.$#'
identifier: arguments.count
count: 1
path: src/Server/RequestHandler/ListResourcesHandler.php

-
message: '#^Result of && is always false\.$#'
identifier: booleanAnd.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListResourcesHandler.php

-
message: '#^Strict comparison using \!\=\= between null and null will always evaluate to false\.$#'
identifier: notIdentical.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListResourcesHandler.php

-
message: '#^Method Mcp\\Capability\\Registry\\ReferenceProviderInterface\:\:getTools\(\) invoked with 2 parameters, 0 required\.$#'
identifier: arguments.count
count: 1
path: src/Server/RequestHandler/ListToolsHandler.php

-
message: '#^Result of && is always false\.$#'
identifier: booleanAnd.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListToolsHandler.php

-
message: '#^Strict comparison using \!\=\= between null and null will always evaluate to false\.$#'
identifier: notIdentical.alwaysFalse
count: 1
path: src/Server/RequestHandler/ListToolsHandler.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:getCompletionProviders\(\) return type has no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addPrompt\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:setDiscovery\(\) has parameter \$excludeDirs with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addResource\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:setDiscovery\(\) has parameter \$scanDirs with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addResourceTemplate\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addPrompt\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addTool\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addResource\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addTool\(\) has parameter \$inputSchema with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addResourceTemplate\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:getCompletionProviders\(\) return type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addTool\(\) has parameter \$handler with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:setDiscovery\(\) has parameter \$excludeDirs with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Method Mcp\\Server\\ServerBuilder\:\:addTool\(\) has parameter \$inputSchema with no value type specified in iterable type array\.$#'
message: '#^Method Mcp\\Server\\ServerBuilder\:\:setDiscovery\(\) has parameter \$scanDirs with no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php
Expand All @@ -456,37 +397,37 @@ parameters:
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$prompts type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$paginationLimit \(int\|null\) is never assigned null so it can be removed from the property type\.$#'
identifier: property.unusedType
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$resourceTemplates type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$paginationLimit is never read, only written\.$#'
identifier: property.onlyWritten
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$resources type has no value type specified in iterable type array\.$#'
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$prompts type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$tools type has no value type specified in iterable type array\.$#'
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$resourceTemplates type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$paginationLimit \(int\|null\) is never assigned null so it can be removed from the property type\.$#'
identifier: property.unusedType
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$resources type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php

-
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$paginationLimit is never read, only written\.$#'
identifier: property.onlyWritten
message: '#^Property Mcp\\Server\\ServerBuilder\:\:\$tools type has no value type specified in iterable type array\.$#'
identifier: missingType.iterableValue
count: 1
path: src/Server/ServerBuilder.php
146 changes: 136 additions & 10 deletions src/Capability/Registry.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,11 +22,13 @@
use Mcp\Event\ResourceListChangedEvent;
use Mcp\Event\ResourceTemplateListChangedEvent;
use Mcp\Event\ToolListChangedEvent;
use Mcp\Exception\InvalidCursorException;
use Mcp\Schema\Prompt;
use Mcp\Schema\Resource;
use Mcp\Schema\ResourceTemplate;
use Mcp\Schema\ServerCapabilities;
use Mcp\Schema\Tool;
use Mcp\Server\RequestHandler\Reference\Page;
use Psr\EventDispatcher\EventDispatcherInterface;
use Psr\Log\LoggerInterface;
use Psr\Log\NullLogger;
Expand Down Expand Up @@ -244,27 +246,92 @@ public function getPrompt(string $name): ?PromptReference
return $this->prompts[$name] ?? null;
}

public function getTools(): array
public function getTools(?int $limit = null, ?string $cursor = null): Page
{
return array_map(fn (ToolReference $tool) => $tool->tool, $this->tools);
$tools = [];
foreach ($this->tools as $toolReference) {
$tools[$toolReference->tool->name] = $toolReference->tool;
}

if (null === $limit) {
return new Page($tools, null);
}

$paginatedTools = $this->paginateResults($tools, $limit, $cursor);

$nextCursor = $this->calculateNextCursor(
\count($tools),
$cursor,
$limit
);

return new Page($paginatedTools, $nextCursor);
}

public function getResources(): array
public function getResources(?int $limit = null, ?string $cursor = null): Page
{
return array_map(fn (ResourceReference $resource) => $resource->schema, $this->resources);
$resources = [];
foreach ($this->resources as $resourceReference) {
$resources[$resourceReference->schema->uri] = $resourceReference->schema;
}

if (null === $limit) {
return new Page($resources, null);
}

$paginatedResources = $this->paginateResults($resources, $limit, $cursor);

$nextCursor = $this->calculateNextCursor(
\count($resources),
$cursor,
$limit
);

return new Page($paginatedResources, $nextCursor);
}

public function getPrompts(): array
public function getPrompts(?int $limit = null, ?string $cursor = null): Page
{
return array_map(fn (PromptReference $prompt) => $prompt->prompt, $this->prompts);
$prompts = [];
foreach ($this->prompts as $promptReference) {
$prompts[$promptReference->prompt->name] = $promptReference->prompt;
}

if (null === $limit) {
return new Page($prompts, null);
}

$paginatedPrompts = $this->paginateResults($prompts, $limit, $cursor);

$nextCursor = $this->calculateNextCursor(
\count($prompts),
$cursor,
$limit
);

return new Page($paginatedPrompts, $nextCursor);
}

public function getResourceTemplates(): array
public function getResourceTemplates(?int $limit = null, ?string $cursor = null): Page
{
return array_map(
fn (ResourceTemplateReference $template) => $template->resourceTemplate,
$this->resourceTemplates
$templates = [];
foreach ($this->resourceTemplates as $templateReference) {
$templates[$templateReference->resourceTemplate->uriTemplate] = $templateReference->resourceTemplate;
}

if (null === $limit) {
return new Page($templates, null);
}

$paginatedTemplates = $this->paginateResults($templates, $limit, $cursor);

$nextCursor = $this->calculateNextCursor(
\count($templates),
$cursor,
$limit
);

return new Page($paginatedTemplates, $nextCursor);
}

public function hasElements(): bool
Expand Down Expand Up @@ -327,4 +394,63 @@ public function setDiscoveryState(DiscoveryState $state): void
}
}
}

/**
* Calculate next cursor for pagination.
*
* @param int $totalItems Count of all items
* @param string|null $currentCursor Current cursor position
* @param int $limit Number requested/returned per page
*/
private function calculateNextCursor(int $totalItems, ?string $currentCursor, int $limit): ?string
{
$currentOffset = 0;

if (null !== $currentCursor) {
$decodedCursor = base64_decode($currentCursor, true);
if (false !== $decodedCursor && is_numeric($decodedCursor)) {
$currentOffset = (int) $decodedCursor;
}
}

$nextOffset = $currentOffset + $limit;

if ($nextOffset < $totalItems) {
return base64_encode((string) $nextOffset);
}

return null;
}

/**
* Helper method to paginate results using cursor-based pagination.
*
* @param array<int|string, mixed> $items The full array of items to paginate The full array of items to paginate
* @param int $limit Maximum number of items to return
* @param string|null $cursor Base64 encoded offset position
*
* @return array<int|string, mixed> Paginated results
*
* @throws InvalidCursorException When cursor is invalid (MCP error code -32602)
*/
private function paginateResults(array $items, int $limit, ?string $cursor = null): array
{
$offset = 0;
if (null !== $cursor) {
$decodedCursor = base64_decode($cursor, true);

if (false === $decodedCursor || !is_numeric($decodedCursor)) {
throw new InvalidCursorException($cursor);
}

$offset = (int) $decodedCursor;

// Validate offset is within reasonable bounds
if ($offset < 0 || $offset > \count($items)) {
throw new InvalidCursorException($cursor);
}
}

return array_values(\array_slice($items, $offset, $limit));
}
}
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